Battery terminal post clamp adapted for connection to an external electric power source or consumer

ABSTRACT

A battery terminal post clamp including a quick coupling device for its connection to a battery terminal post and operating means for operating the quick coupling device, said operating means being provided with an insulated handle means. The insulated handle means (320 is connected to the operating means (120 by lost motion means (37, 38, 39, 40) allowing the handle means (32) to be moved a limited distance without operating the quick coupling device to disengage said battery terminal post, said limited distance enabling access to metallic parts of the clamp.

The present invention concerns a battery terminal post clamp including ametallic quick coupling device for its connection to a battery terminalpost and an operating means for operating the quick coupling device.

Battery terminal post clamps of this general kind are described in a. o.U.S. Pat. Nos. 1,930,722, 2,185,419, 2,257,013, 3,324,266 and SE-A-129178.

Another example of such a battery terminal post clamp is described inEuropean Patent EP-B-0 027 438 and corresponding Swedish and patentsSE-C-7908486-9 and U.S. Pat. No. 4,385,796, respectively. The batteryterminal post clamp of these patents includes a first substantiallyU-shaped part having a bottom portion and parallel legs extendingtherefrom, and a second likewise substantially U-shaped part having abottom portion and parallel legs extending therefrom. The bottomportions of the two parts are complementary shaped so as tosubstantially conform to the shape of a battery terminal post in theoperative position of the clamp, while the legs of the two parts aremutually parallel. The two parts are adapted to be displaced relative toeach other to and from the operative position by means of an overcenterdevice connected to the two parts. The overcenter device includes asubstantially U-shaped operating lever, by means of which the two partsare displaced relative to each other in order to make the clamp engageor disengage a battery terminal post.

Not only the two parts but also the operating lever are manufactured ofmetal. In order to protect a user against electric shocks and also toavoid inadvertent short circuits caused by e.g. dropped metallic tools,the operating lever, in a commercial embodiment this known batteryterminal post clamp, is accomodated in a shell-like casing of insulatingmaterial, such as a molded synthetic resin. In the operative, closedposition of the battery terminal post clamp, this casing, serving alsoas a handle for the lever, covers not only the operating lever, but alsothe two parts engaging a battery terminal post and portions thereofconnected to an electric cable. The casing is rigidly attached to theoperating lever such that movement of the casing is positivelytransferred to the operating lever.

In some instances, such as a low voltage condition in the battery towhich the battery terminal post clamp is connected, or, in another,external battery, there is a need to temporarily connect a second cable(a so called starting-cable) to each of the battery terminal posts inorder to connect them to the respective poles of an outer electricsource, or, the terminal posts of the external battery, respectively.This may be the case when attempts to start the motor of a motor vehiclefail due to a low voltage condition in the battery of the vehicle.

In order to connect a second cable to the known battery terminal postclamp having a casing as described, or , to the battery terminal post towhich it is connected, it is necessary to disengage the clamp by raisingthe casing and the lever attached thereto to make a metallic part of theclamp, or, the battery terminal post itself accessible. Apart from thework involved, such disengagement may cause serious damage to theelectrical circuit of a motor vehicle if the electrical connection isinterrupted, particularly in cases where such circuitry includes analternating current generator, and the motor of the vehicle driving thegenerator is running.

Also the battery terminal post clamps described in the patents initiallycited include metallic battery terminal post engaging parts as well asmetallic operating levers or other operating means for engaging anddisengaging the clamps. If these known battery terminal post clamps wereprovided with insulating handle means as described above they too wouldsuffer from the same disadvantages.

Consequently, there is a need for a battery terminal post clamp enablingelectrical connection of a second cable to a battery terminal postwithout disengaging the clamp.

The object of the present invention, thus, is to provide a batteryterminal post clamp of the kind initially stated and having an insulatedhandle means with means enabling such connection.

In a battery terminal post clamp including a quick coupling device forits connection to a battery terminal post and an operating means foroperating the quick coupling device, said operating means being providedwith an insulated handle means, this object has been achieved in thatthe insulated handle means is connected to the operating means by lostmotion means allowing the handle means to be moved a limited distancewithout operating the quick coupling device to disengage said batteryterminal post, said limited distance enabling access to metallic partsof the clamp.

An embodiment of the present invention, based on the battery terminalpost clamp described in EP-B-0 027 438 cited above, will now bedescribed, reference being made to the accompanying drawings, wherein:

FIG. 1 is a perspective view showing a battery terminal post clamp ofthe known kind in an open position;

FIG. 2 is a side view showing the mechanism of a battery terminal postclamp according to the present invention in an open position;

FIG. 3 is a perspective view showing the operating lever of the batteryterminal post clamp according to FIG. 2;

FIG. 4 is a longitudinal section through the battery terminal post clampaccording to the present invention in an entirely open, disengagedposition;

FIG. 5 is a view similar to that of FIG. 4 showing the battery terminalpost clamp with its handle in a raised position but the mechanism of theclamp still in an engaged position, the mechanism being shown withdash-dotted lines;

FIG. 6 is a view similar to that of FIG. 5 showing the battery terminalpost clamp in a closed position;

FIG. 7 is a view in the direction of arrow VII in FIG. 6;

FIG. 8 is a section through the handle only taken along line VIII--VIIIin FIG. 6; and

FIG. 9 is a section through the handle only taken along line IX--IX inFIG. 6.

The battery terminal post clamp according to the European Patentmentioned comprises a first part 1 and a second part 2, which aredisplaceable relative to each other, said parts preferably being punchedand bent sheet metal parts. An electric cable connection 3 is formedintegrally with the second part 2 and is adapted to be clamped around abattery cable (not shown). Parts 1 and 2 are shaped with cooperatingsubstantially U-shaped portions 4 and 5, respectively, defining in theoperative state of the battery terminal post clamp a substantiallyfrusto-conical space conforming to the shape of an ordinary batteryterminal post. Each of the parts has mutually parallel legs 6,7 and 8,9,respectively, extending from the respective U-shaped portion. In orderto achieve mutual guidance during relative displacement of the partstowards and from each other, the legs 6, 7 of the first part 1 areprovided with guide pockets 10,11, respectively, through which extendthe legs 8,9 of the second part 2.

A substantially U-shaped operating lever 12, comprising two generallyparallel legs 13,14 and a bridging web portion 15, has the ends of itslegs extending outside of the legs 8,9 of part 2 and by means of holes16,17 provided therein pivoted on a shaft 18 extending between holes19,20 at the ends of the legs 8,9 of the second part 2. A substantiallyU-shaped link 21 having a middle portion 22 and two parallel legs 23,24extending therefrom is introduced with its middle portion 22 throughholes 25,26, respectively, at the free ends of the legs 6 and 7 of thefirst part 1. Inwardly bent ends 27,28, respectively, of the legs 23,24are engaged in corresponding holes 29,30, respectively, in the legs13,14 of the operating lever. In the operative, closed position of thebattery terminal post clamp the holes 29,30 and, consequently, theinwardly bent ends 27,28 of the legs 23,24 of link 21, are located asmall distance below an imaginary plane through holes 19,20 and 25,26,and consequently, shaft 18 and middle portion 22 of link 21. There iscreated, thus, an overcentre mechanism controlling the relativedisplacement of parts 1 and 2 by raising or lowering the operating lever12, said mechanism having a deadpoint when the inwardly bent ends 27,28of legs 23,24 pass through the imaginary plane mentioned.

In a commercial embodiment of the known battery terminal post clampdescribed, an insulating handle 31 of molded plastics material ismounted on the operating lever 12 such that no metallic part of thebattery terminal post clamp is accessible when the clamp is engaged on abattery terminal post and such that the operating lever positivelyfollows any movement of the handle. As initially mentioned, whenoperating the handle in an opening direction, this causes immediatedisengagement of the battery terminal post clamp. In order to avoid thisdrawback, the battery terminal post clamp of the present invention isprovided with a handle which allows a certain amount of opening movementbefore the mechanism is operated to disengage the battery terminal postclamp.

In order to achieve this feature the battery terminal post clamp of thepresent invention is provided with a substantially shell-like handle 32preferably being a molded plastics part. Close to one end of its opposedlongitudinal walls 33,34 the handle is provide with inwardly open holes35,36, respectively, said holes engaging the ends of shaft 18 extendingthrough legs 8,9 of part 2 and legs 13,14 of operating lever 12. Sincethis is the only positive engagement between the metallic parts of thebattery terminal post clamp and its handle, the handle is swingableabout shaft 18 relative to the metallic parts.

In order to transfer swinging motion of the handle 32 to the operatinglever 12, the operating lever and the handle are provided withcooperating lost motion means. On the operating lever 12 such meanscomprises outwardly bent ears 37,38 integral with the legs 13 and 14,respectively, and being located close to the leg bridging web portion15. For abutting cooperation with the ears 37,38 in the openingdirection of the handle (clockwise in FIG. 5) the longitudinal walls33,34 of handle 32 are interiorly provided with inwardly protrudingabutments 39,40. In the closing swinging direction of the handleabutment takes place between the upper interior wall 41 of the handle,or, preferably, longitudinally directed protrusions 42,43 integral withthis wall, and the ears 37,38. The angle defined by the upper wall 41,or, its protrusions 42,43, the shaft 18, and the abutments 37,38, thus,is the lost motion angle within which the handle may swing withoutoperating the operating lever when being moved from its closed positionaccording to FIG. 6.

As appears from FIG. 6 the abutments 39,40 preferably have inclinedupper abutment surfaces, the inclination being such as to obtain surfacecontact with the undersides of ears 37,38 when the handle reaches theend of its lost motion travel (FIG. 5).

In order to retain the handle in its closed position (FIG. 6) thelongitudinal walls 33,35 thereof are interiorly provided with ribs 44,45(FIGS. 7 and 9) extending in the longitudinal direction of the handleand protruding inwardly so as to snap over the legs 23,24 of link 21when bringing the handle to its closed position. Such snapping action ofribs 44,45 is enabled due to the handle being made from a relativelyelastic thermoplastic material.

To accomodate an electric cable attached to the connection 3 when thehandle is in the closed position shown in FIG. 6, the handle 32, as wellas handle 31 shown in FIG. 1, is provided with an opening 46.

As is apparent from the foregoing description, the handle 32 of thebattery terminal post clamp according to the present invention may beraised from the closed position shown in FIG. 6 to the position shown inFIG. 5, thereby enabling access to metallic parts of the clamp, such asfor temporary connection of a second cable, without affecting theengagement of the battery terminal post clamp to a battery terminalpost.

I claim:
 1. A battery terminal post clamp, comprising:means forreleasably clamping the post, said clamp means being connectable to anelectric cable; a lever for actuating said clamp means, said lever beingpivotally connected at one of its ends to said clamp means and beingpivotable between a closed position wherein said clamp means clamps thepost and an open position wherein said clamp means releases the post; anelectrically insulated handle pivotally connected to said lever; andlost motion means for allowing said handle to pivot from a coverposition covering said clamp means, through a limited angle beforeactuating said lever to said open position, said handle uncovering saidclamp means to expose metallic parts thereof at said limited angle. 2.The battery terminal post clamp according to claim 1, wherein the heightof the clamp means is exposed at one end of the clamp means when saidhandle pivots to said limited angle.
 3. A battery post clamp accordingto claim 1, characterized in that said lost motion means comprisescooperating respective portions of said handle and of said lever, saidportions being spaced from said one end of the said handle and said endof said lever, respectively.
 4. A battery terminal post clamp accordingto claim 1, characterized in that said respective cooperating portionsare abutments on said handle and on said lever.
 5. A battery terminalpost clamp according to claim 4, characterized in that said portion ofsaid handle is integrated in said handle.
 6. A battery terminal postclamp according to claim 4, characterized in that said portion of saidlever comprises a flap protruding from said lever.
 7. A battery terminalpost clamp according to any one of the preceding claims, characterizedin that said handle includes means for interlocking with portions of thesaid clamp means in the cover position of said handle to preventunintended opening thereof.
 8. A battery terminal post clamp including aquick coupling device for its connection to a battery terminal post andoperating means for operating the quick coupling device, said operatingmeans being provided with an insulated handle means, characterized inthat the insulated handle means is connected to the operating means bylost motion means allowing the handle means to be moved a limiteddistance without operating the quick coupling device to disengage saidbattery terminal post, said limited distance enabling access to metallicparts of the clamp, said handle means including means for interlockingwith portions of said quick coupling device in the closed position ofsaid handle means to prevent unintended opening thereof, wherein saidinterlocking means comprises inwardly protruding ribs integral with saidhandle means.